Carbon nanotubes (CNTs) have been proposed for numerous applications due to their excellent electrical conductivity values and high mechanical strength. In the realm of electrical devices, carbon nanotubes can be of particular interest due to their ability to display non-volatile memory effects. That is, carbon nanotubes can be cycled between high and low electrical conductivity states though application of voltage pulses having a sufficient magnitude, such that the attained conductivity state is maintained once the voltage pulse ceases. Maintenance of the attained conductivity state allows the carbon nanotubes to function as a memory when in an electrical device, where a high conductivity state of the carbon nanotubes represents an ON state and a low conductivity state of the carbon nanotubes represents an OFF state.
Vertical orientations of electrical devices are highly desirable in the electronics industry, since vertical orientations can allow a higher density of electrical devices to be packed per unit area compared to a horizontal orientation. In addition, vertical orientations can more readily facilitate the construction of crossbar electrical device arrays. Vertical design strategies are compatible with deposition and patterning techniques that are commonly used throughout the modern electronics industry. Although these techniques can be successfully used for many types of electrical devices, they can be somewhat incompatible with carbon nanotubes. Specifically, many commonly used deposition and patterning techniques, particularly metal deposition techniques, can damage the structure of carbon nanotubes, thereby increasing their switching voltages and reducing their ability to switch. In addition, there can be an increased incidence of electrical shorting due to unwanted metal-to-metal contact when carbon nanotubes are used in electrical devices due to metal filament formation through the carbon nanotubes. As a result, fabrication of vertically oriented electrical devices containing carbon nanotubes can be problematic, both in terms of reliability and achieving desired device characteristics.
In view of the foregoing, techniques that allow carbon nanotubes to be passivated while maintaining their favorable electrical properties, particularly when disposed in vertically oriented electrical devices, would be of considerable benefit in the art. Electrical devices manufactured using these techniques would represent a significant advance in the electronics industry. The present disclosure satisfies the foregoing needs and provides related advantages as well.